/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.connector.kafka.source.enumerator;

import org.apache.flink.connector.base.source.utils.SerdeUtils;
import org.apache.flink.connector.kafka.source.split.KafkaPartitionSplit;
import org.apache.flink.connector.kafka.source.split.KafkaPartitionSplitSerializer;
import org.apache.flink.core.io.SimpleVersionedSerializer;

import java.io.IOException;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

/**
 * The {@link org.apache.flink.core.io.SimpleVersionedSerializer Serializer} for the enumerator state of
 * Kafka source.
 */
public class KafkaSourceEnumStateSerializer implements SimpleVersionedSerializer<KafkaSourceEnumState> {

	private static final int CURRENT_VERSION = 0;

	@Override
	public int getVersion() {
		return CURRENT_VERSION;
	}

	@Override
	public byte[] serialize(KafkaSourceEnumState enumState) throws IOException {
		return SerdeUtils.serializeSplitAssignments(
				enumState.getCurrentAssignment(),
				new KafkaPartitionSplitSerializer());
	}

	@Override
	public KafkaSourceEnumState deserialize(int version, byte[] serialized) throws IOException {
		if (version == 0) {
			Map<Integer, Set<KafkaPartitionSplit>> currentPartitionAssignment =
					SerdeUtils.deserializeSplitAssignments(
							serialized,
							new KafkaPartitionSplitSerializer(),
							HashSet::new);
			return new KafkaSourceEnumState(currentPartitionAssignment);
		}
		throw new IOException(String.format("The bytes are serialized with version %d, " +
				"while this deserializer only supports version up to %d", version, CURRENT_VERSION));
	}
}
